1. Field of the Invention
The present invention relates to art for correcting types of image characteristics such as tone, hue, chroma and the like of a motion image captured as digital data.
2. Description of the Related Art
Art heretofore has been proposed for correcting the tone and the like of a motion image in real time. For example, Japanese Laid-Open Patent No. H7-212620 discloses a motion image processor which performs simple tone correction in real time. However, the correction of a motion image by the device of this disclosure is limited, and correction suitable for the characteristics of each frame of the image cannot be accomplished.
On the other hand, Japanese Laid-Open Patent No. 2000-57335 discloses art for correcting a still image by determining the feature quantity of tone, hue, chroma and the like of an image, and performing high-level correction based on the feature quantities.
A great deal of calculations are necessary for correction when the image of each frame of a motion image is handled as a still image to achieve high-level correction of the still image which is applied to correct the motion image. For example, to process a motion image in real time, for example, 33 ms or less is required to process one frame in a motion image of 30 fps (30 frames per second). Accordingly, development of expensive processors are required to apply the correction method used for still images to real time correction of motion images.
For this reason, when performing high-level correction of a motion image, processing is executed in real time after the motion image has once been stored on a recording medium such as a hard disk or the like. In this case, a long time is also required for processing due to the quantity of calculations required to correct the entire motion image.